CHECKING SERVICE, APPARATUS AND METHOD FOR CHECKING DEGRADATION OF LIGHTNING ARRESTOR BY HARMONIC ANALYSIS

摘要

PURPOSE: An apparatus for checking degradation of a lightning arrestor by harmonic analysis is provided to measure the degrading state of a lightning arrestor by using a current measuring circuit and an impedance matching circuit. CONSTITUTION: A current measuring circuit(31) passes through an impedance matching circuit(42) for accurately processing the current information inputted from a clamp type current transformer(22). The circuit comprises a part which can minimize the load of the current transformer(22). The current information from which noises are removed passes through HPF(42) and LPF(43), and passes frequency band widths which are needed for determining the degradation of the lightning arrestor. The current information which has passed through HPF(42) and LPF(43) passes through an A/D convertor(44) and is converted into digital signals which is transferred to a degradation determining system(33).